1148 infection control & hospital epidemiology october 2017, vol. 38, no. 10


textiles demonstrate activity against pathogens such as S. aureus, Candida albicans, Acinetobacter spp., vegetative Clostridium difficile, and Klebsiella pneumoniae.8–10 However, data to support the use of antimicrobial-impregnated textiles in clinical practice are limited.11–15 We designed the Antimicrobial Scrub Contamination and


Transmission (ASCOT) Trial (1) to determine whether antimicrobial-impregnated surgical scrubs decrease the burden of HCP clothing contamination compared to standard surgical scrubs following a 12-hour intensive care unit (ICU) shift and (2) to characterize the transmission dynamics of epidemiologically-important pathogens among the patient, the environment, and the HCP, a group we labeled the “transmission triangle.”


methods Study Design and Participants


We performed this blinded, 3-arm, randomized controlled trial with crossover design in 2 ICUs at Duke University Hospital between June 15, 2015, and January 10, 2016. The study included 1 control arm and 2 intervention arms. Nurses wore standard cotton-polyester surgical scrubs in the control arm. In the Scrub 1 intervention arm, nurses wore surgical scrubs that contained a


complex element compound with a silver alloy embedded in its fibers. In the Scrub 2 intervention arm, nurses wore surgical scrubs impregnated with an organosilane-based quaternary ammonium and a hydrophobic fluoroacrylate copolymer emulsion. Nurses participated in each arm during 3 consecutive 12-hour shifts in the ICU. Study personnel laundered all study scrubs 5 times and delivered them to nurse participants in plastic bags. Nurses donned the study scrubs at home and presented to work according to their routines. In this study, we enrolled nurses from the medical ICU and


surgical ICU at Duke University Hospital, a 936-bed tertiary-care hospital in Durham, North Carolina, where ICU nurses typically care for patients in 2 ICU rooms each shift. All nurses working in themedical ICU or the surgical ICU were eligible for enrollment. Data from enrolled nurses who failed to complete all 3 shifts were excluded. Patients known to be colonized or infected with any multidrug-resistant pathogen were routinely placed on contact precautions, during which all HCPs wore gowns and gloves upon entry into the room. These ICUs did not perform routine active surveillance during the study period. The Duke University Health System Institutional Review


Board approved the study. Nurses provided written informed consent. We received a waiver of informed consent to collect data and specimens from the patients receiving care from enrolled nurses. The study is registered on ClinicalTrials.gov (NCT 02645214).


Randomization and Blinding


After obtaining consent from the nurse subject, the study coordinator provided the nurse with 3 sets of scrubs.Nurses were


blinded to the type of scrub. Brands and labelswere removed from scrubs; all scrubs were “Duke blue” in color. The study coordinator provided written and verbal instructions on which scrubs to wear with each shift. Nurse participants were randomized to 1 of 6 sequences of scrubs (Supplementary Table 1). The nurses wore a different scrub type during each of the 3 12-hour shifts, so each nurse participated in each study arm in a 1:1:1 ratio. The study team was not blinded during specimen and data collection. However, microbiology personnel were blinded to study arm allocation during the analysis of specimens.


Procedures


The study coordinator arrived at the ICU prior to the beginning of each shift to obtain cultures from each nurse’s scrubs (sleeve, abdomen, and pocket) as well as specified “high touch” surfaces (bedrail, bed, and supply cart) in each of that nurse’s2assigned rooms (Supplementary Figure 1). The coordinator repeated the process of obtaining samples from each nurse’sscrubs andassigned roomsatthe endofthe nurse’s shift. The study coordinator also obtained cultures from each patient who received care from a participating nurse during that shift. Specimens were collected from the anterior nares, the perirectal area, and from the integument (i.e., wounds, drains, or axilla). Microbiological methods are provided in detail in the Supplementary Material. Cultures from each nurse/patient/room grouping were analyzed for the presence of similar species. A potential transmission event or “acquisition” was defined as the new identification of a target pathogen on nurse clothing, the patient, or the environment. A confirmed transmission event or “transmission” was defined as an acquisition event for which a source from the transmission triangle could be identified and confirmed. Organisms involved in acquisition events were analyzed for transmission events using pulsed-field gel electrophoresis (PFGE; see Supplementary Material).16 Finally, each nurse completed a 4-question survey at the


end of the shift to describe how the scrubs worn during the shift compared to their standard work scrubs. Ultimately, each nurse answered 3 surveys, corresponding with each arm in the study.


Outcomes


The primary outcome of our study was the change in total contamination on nurse scrubs, measured as the sum of colony-forming units (CFU) of bacteria identified on nurse scrubs from each clothing location. The following predetermined secondary outcomes were measured: (1) the presence or absence of individual target pathogens; (2) the number and proportion of acquisitions and transmission events; and (3) HCP perceptions of clothing.


Statistical Analysis


This prospective, blinded, randomized trial was designed to test the hypothesis that antimicrobial-impregnated scrubs


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116  |  Page 117  |  Page 118  |  Page 119  |  Page 120  |  Page 121  |  Page 122  |  Page 123  |  Page 124  |  Page 125  |  Page 126  |  Page 127  |  Page 128  |  Page 129  |  Page 130  |  Page 131  |  Page 132  |  Page 133  |  Page 134  |  Page 135  |  Page 136  |  Page 137  |  Page 138  |  Page 139  |  Page 140  |  Page 141  |  Page 142  |  Page 143  |  Page 144